1. Field of the Invention
This invention concerns a distillate fuel composition containing a mono alkyl substituted derivative of thiadiazole and its use to reduce the formation of intake valve deposits in an internal combustion engine.
2. Description of Related Art
Various substituted derivaties of thiadiazoles have been used to inhibit corrosion in lubricating oils. For example,
U.S. Pat. No. 2,703,784 discloses a lubricating oil containing an oil soluble reaction product of an aldehyde, a mercaptan, and 2,5-dimercapto-1,3,4-thiadiazole.
U.S. Pat. No. 2,765,289 discloses a lubricating oil containing an oil soluble reaction product of an aldehyde, a diarylamine, and 2,5-dimercapto-1,3,4-thiadiozole.
U.S. Pat. No. 2,850,453 discloses a lubricating oil comprising an oil soluble reaction product obtained by reacting 2,5-dimercapto-1,3,4-thiadiazole, an aldehyde, and an organic hydroxy compound.
U.S. Pat. No. 2,719,126 discloses a lubricating oil containing an oil soluble polysulfide derivative of 2,5-dimercapto-1,3,4-thioadiazole.
U.S. Pat. No. 2,799,651 discloses a lubricating oil comprising an oil soluble derivative of 2-mercapto-4-phenyl-5-thione-1,3,4-thiadiazole.
U.S. Pat. No. 2,764,547 discloses a lubricating oil comprising an oil soluble reaction product of 2,5-dimercapto-1,3,4-thiadiazole and an unsaturated cyclic compound.
U.S. Pat. No. 2,799,652 discloses a lubricating oil containing an oil soluble product obtained by reacting 2,5-dimercapto-1,3,4-thiadiazole with an unsaturated ketone.
In addition, several patents disclose the use of other substituted derivatives of thiadiazoles in lubricating oils and in fuels wherein the thiadiazoles contain di- or poly-sulfides. (See, for example, U.S. Pat. Nos. 2,719,126; 3,683,561; 4,104,179, and GB No. 1,474,048).
However, none of these patents suggest the particular classes of thiadiazole derivatives disclosed herein or their effectiveness in reducing the formation of intake valve deposits.